Submission #570578

#	Time	Username	Problem	Language	Result	Execution time	Memory
570578		YouAreMyGalaxy	Dreaming (IOI13_dreaming)	C++17	100 / 100	111 ms	18760 KiB

dreaming

//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#include "dreaming.h"
#define TASK "TESTCODE"
#define Log2(x) 31 - __builtin_clz(x)
using namespace std;
const int N = 1e5;
vector<pair<int, int> > Adj[N];
int dp[N], f[N], res;
bool visited[N];
void preDFS(int u, int p)
{
    visited[u] = true;
    for (auto x : Adj[u])
    {
        int v = x.first, w = x.second;
        if (v == p)
        {
            continue;
        }
        preDFS(v, u);
        dp[u] = max(dp[u], dp[v] + w);
    }
}
int DFS(int u, int p)
{
    int ret = max(f[u], dp[u]);
    res = max(res, f[u] + dp[u]);
    int t[2], id[2];
    t[0] = t[1] = id[0] = id[1] = 0;
    for (auto x : Adj[u])
    {
        int v = x.first, w = x.second;
        if (v == p)
        {
            continue;
        }
        f[v] = f[u] + w;
        for (int i = 1; i >= 0; -- i)
        {
            if (t[i] < dp[v] + w)
            {
                for (int j = 0; j < i; ++ j)
                {
                    t[j] = t[j + 1];
                    id[j] = id[j + 1];
                }
                t[i] = dp[v] + w;
                id[i] = v;
                break;
            }
        }
    }
    for (auto x : Adj[u])
    {
        int v = x.first, w = x.second;
        if (v == p)
        {
            continue;
        }
        for (int i = 1; i >= 0; -- i)
        {
            if (id[i] != v)
            {
                f[v] = max(f[v], t[i] + w);
                break;
            }
        }
        ret = min(ret, DFS(v, u));
    }
    return ret;
}
int travelTime(int n, int m, int l, int A[], int B[], int T[])
{
    for (int i = 0; i < m; ++ i)
    {
        int u = A[i], v = B[i];
        Adj[u].push_back({v, T[i]});
        Adj[v].push_back({u, T[i]});
    }
    int t[3];
    t[0] = t[1] = t[2] = 0;
    int cnt = 0;
    for (int u = 0; u < n; ++ u)
    {
        if (!visited[u])
        {
            ++ cnt;
            preDFS(u, -1);
            int x = DFS(u, -1);
            for (int i = 2; i >= 0; -- i)
            {
                if (t[i] < x)
                {
                    for (int j = 0; j < i; ++ j)
                    {
                        t[j] = t[j + 1];
                    }
                    t[i] = x;
                    break;
                }
            }
        }
    }
    if (cnt >= 2)
    {
        res = max(res, t[1] + t[2] + l);
    }
    if (cnt >= 3)
    {
        res = max(res, t[0] + t[1] + 2 * l);
    }
    return res;
}

• Subtask 1: 14 / 14
• Subtask 2: 10 / 10
• Subtask 3: 23 / 23
• Subtask 4: 18 / 18
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23